Target location designation apparatus

ABSTRACT

Apparatus and method are disclosed for guiding a payload to a target location. The apparatus comprises a laser radiation source, a laser radiation reflecting arrangement for generating substantially spatially homogeneous reflected laser radiation, an activator for activating the radiation source to generate laser radiation and an electrical power source for powering the apparatus.

The present invention relates to target location designation apparatusand particularly, but not exclusively to target location designationapparatus for guiding a payload to a target location.

When payloads are deployed from vehicles, it is known to guide thepayload to a desired target location using location designators. Knownlocation designators typically comprise a laser source which is used toilluminate the target location from a remote position. The laserradiation is generally directed at the target location such that laserradiation reflected from the target location, such as a building, iscollected by a sensor disposed upon the payload and utilised to guidethe payload toward the target location.

The known designators involve illuminating the target locations from anearby location and since the sensor associated with the payload isreceptive to reflected laser radiation, a clear line of sight isrequired between the designator and the target location. Moreover, thedesignation of a target location in this manner requires the location ofan operator local to the target location to operate the designator. Thisis often unsuitable, particularly where the target location is cited ina hostile or harsh environment, or in situations where the payload isdesigned to explode on reaching the target location.

We have now devised an improved target designation apparatus.

In accordance with a first aspect of the present invention there isprovided target location designation apparatus for guiding a payload toa target location, the apparatus comprising:

-   -   a laser radiation source,    -   a laser radiation reflecting arrangement for generating        substantially spatially homogeneous reflected laser radiation,    -   an electrical power supply for powering the laser radiation        source, and    -   an activator for electrically coupling the power supply with the        laser radiation source to activate the laser radiation source.

In an embodiment, the activator comprises a receiver which is arrangedto receive a trigger signal for activating the laser radiation source.The receiver may be receptive to a radio signal generated from a remotelocation, such that the laser radiation source may be activated withoutthe requirement for a line of sight to the target designation apparatus.In an alternative embodiment, the activator may comprise a timer whichis arranged to activate the laser radiation source at a predeterminedtime, or following a pre-determined time delay following deployment ofthe apparatus.

The electrical power supply may comprise a battery or similar.Alternatively, or in addition thereto, the electrical power supply maycomprise or further comprise a solar panel.

The laser radiation reflecting arrangement is arranged to simulate laserradiation which is reflected off objects, such as buildings and terrain,since the sensors disposed on payloads are generally sensitive to thisreflected radiation when homing in on the intended target. Preferably,the laser radiation reflecting arrangement comprises a grating.Alternatively, the reflecting arrangement may comprise a radiationdispersion element for simulating reflected laser radiation.

Preferably, the laser radiation source is configured for generatinglaser pulses. Alternatively, the laser radiation source may beconfigured to generate continuous laser radiation.

In a further embodiment, the laser radiation source may comprise aplurality of separate sources for generating the substantially spatiallyhomogeneous reflected laser radiation through an increased angularrange.

In accordance with a second aspect of the present invention there isprovided a method of guiding a payload to a target location, the methodcomprising the steps of:

-   -   locating a target location designation apparatus according to        the first aspect at the target location, and    -   activating the laser radiation source of the apparatus to cause        substantially spatially homogeneous reflected laser radiation to        be generated for guiding the payload to the target location.

The method may comprise activating the laser radiation source at apre-determined time or following a pre-determined time delay, using atimer.

Alternatively, the method may comprise activating the laser radiationsource using a trigger signal from a transmitter remotely located to theapparatus.

Further preferred features of the method of the second aspect maycomprise one or more of the preferred features of the target locationdesignation apparatus of the first aspect.

Embodiments of the present invention will now be described by way ofexample only and with reference to the accompanying drawings, in which:

FIG. 1 is a schematic illustration of a target location designationapparatus according to an embodiment of the present invention;

FIG. 2 is a flow chart outlining the steps associated with a method ofdesignating a target location according to any embodiment of the presentinvention.

Referring to FIG. 1 of the drawings, there is illustrated a targetlocation designation apparatus 10 according to an embodiment of thepresent invention for guiding a payload 20 to a target location 30. Theapparatus 10 comprises a housing 11, a laser radiation source 12disposed within the housing 11 and a laser radiation reflectingarrangement 13 which is arranged to reflect the laser radiation incidentthereon from the laser radiation source 12 to create substantiallyspatially homogenous laser radiation which is output through a window 14disposed within the housing 11. The laser radiation output from thehousing 11 is arranged to simulate laser radiation which may bereflected off objects such as buildings, vehicles (not shown) and thelike, and is arranged to guide payloads 20 to the desired targetlocation 30.

The laser radiation source 12 may comprise a diode laser, and may betuneable to generate laser radiation at a preferred lasing wavelength,such as an infra-red wavelength or a wavelength in the visible region ofthe spectrum. The source 12 may also be operable to generate continuouslaser radiation or alternatively pulsed laser radiation. In this manner,the reflected laser radiation which is output from the housing 11 may beappropriately configured according to the particular sensor 21 used onthe payload 20.

The apparatus 10 further comprises an electrical power supply 15, suchas a battery arrangement 15 a or similar, or alternatively a solar panel15 b for acquiring electrical power during periods of sunlightillumination. However, it is also envisaged that the solar panel 15 bmay be used to charge the battery arrangement 15 a, and as such thebattery arrangement 15 a may be used in conjunction with the solar panel15 b. The power supply 15 to the laser radiation source is controlled byan activator 16 which is arranged to electrically couple the laserradiation source 12 with the electrical power supply 15. The activator16 is disposed within the housing 11 and in an embodiment, the activator16 may comprise a receiver 16 a for receiving a trigger signal from aremote source. Upon receiving the signal, the activator 16 is arrangedto electrically couple the power supply 15 with the laser radiationsource 15. For example, the receiver 16 a may be arranged to receive aradio signal from a transmitter (not shown) remotely located to theapparatus 10. In an alternative embodiment, the activator 16 maycomprise a timer 16 b which may be configured to electrically couple thelaser radiation source 12 with the power supply 15 and thus cause thelaser radiation source 12 to switch to an operational state at aparticular time. Alternatively, the timer 16 b may be arranged to switchthe laser radiation source 12 to an operational state after apre-determined time delay.

In order to simulate the reflection of laser radiation that is currentlyused to guide payloads 20 to the desired target location 30, the laserradiation reflecting arrangement 13 may comprise a grating 13 a or adispersive element 13 b. The reflecting arrangement 13 is disposedwithin the housing 11 and the laser radiation from the source 12 isincident upon the reflecting arrangement 13 such that the radiationreflected therefrom is output through the window 14 of the housing 11such that it can be detected and thus utilised by the sensors 21disposed on payloads 20 for guiding the payloads 20 to the targetlocation 30. In a further embodiment, it is envisaged that the laserradiation source 12 may comprise a plurality of separate laser radiationsources (not shown) for separately illuminating the reflectingarrangement 13, such that the radiation reflected therefrom may beoutput through the window 14 through a greater angular range and thusprovide for an improved and/or earlier detection by the payload sensor21.

Referring to FIG. 2 of the drawings, there is illustrated a flowchartoutlining the steps associated with a method 100 of designating a targetlocation 30 according to an embodiment of the present invention. Whendesignating a target location 30 using the apparatus 10, the apparatus10 is physically sited at the desired target location 30 at step 101, inadvance of the required delivery time of the payload 20.

Once the apparatus 10 has been appropriately sited, then the activator16 may be activated at step 102, to electrically couple the power supply15 with the laser radiation source 12 to cause laser radiation to begenerated. As discussed above, in the case that the activator 16comprises a timer 16 b, the timer 16 b may be activated upon siting theapparatus 10 at the target location 30 to commence a countdownrepresentative of the desired time delay. Alternatively, the timer 16 bmay simply be used to electrically couple the power supply 15 with thelaser radiation source at a desired time. In a further alternative, inthe case that the activator 16 comprises a receiver 16 a, then anoperator (not shown) may cause the activator 16 to electrically couplethe laser radiation source 12 with the power supply 15 by transmitting atrigger signal to the receiver 16 a using a transmitter (not shown)remotely located to the receiver 16 a. In each of the above embodiments,it is envisaged that the apparatus 10 will remain inert for a period oftime after being sited at the target location 30.

Upon activating the activator 16, the apparatus 10 is arranged to outputsimulated, reflected laser radiation through the window 14 disposedwithin the housing 11 at step 103, so that the reflected radiation canbe detected by a sensor 21 on the intended payload 20, so that thepayload 20 can be guided to the target location 30.

The apparatus 10 and method 100 according to the above describedembodiments thus obviate any requirement for a clear line of sight tothe target location 30 for the designation thereof and further removesthe necessity for an operator of the designator to be located in thevicinity of the target location 30.

1. Target location designation apparatus for guiding a payload to atarget location, the apparatus comprising: a laser radiation source; alaser radiation reflecting arrangement for generating substantiallyspatially homogeneous reflected laser radiation; an electrical powersupply for powering the laser radiation source; and an activator forelectrically coupling the power supply with the laser radiation sourceto activate the laser radiation source.
 2. Target location designationapparatus according to claim 1, wherein the activator comprises areceiver which is arranged to receive a trigger signal for activatingthe laser radiation source.
 3. Target location designation apparatusaccording to claim 1, wherein the activator comprises a timer, which isarranged to activate the laser radiation source at a predetermined time,or following a pre-determined time delay.
 4. Target location designationapparatus according to claim 1 wherein the electrical power sourcecomprises a battery.
 5. Target location designation apparatus accordingto claim 1, wherein the electrical power source comprises a solar panel.6. Target location designation apparatus according to claim 1 whereinthe laser radiation reflecting arrangement is arranged to simulate laserradiation which is reflected off objects.
 7. Target location designationapparatus according to claim 1 wherein the laser radiation reflectingarrangement comprises a grating.
 8. Target location designationapparatus according to claim 1, wherein the reflecting arrangementcomprises a laser radiation dispersion element for simulating reflectedlaser radiation.
 9. Target location designation apparatus according toclaim 1 wherein the laser radiation source is configured to generatelaser pulses.
 10. Target location designation apparatus according toclaim 1, wherein the laser radiation source is configured to generatecontinuous laser radiation.
 11. Target location designation apparatusaccording to claim 1 comprising a plurality of separate laser radiationsources.
 12. A method of guiding a payload to a target location, themethod comprising: locating a target location designation apparatusaccording to claim 1 at the target location, and activating theapparatus to cause substantially spatially homogeneous reflected laserradiation to be generated for guiding the payload to the targetlocation.
 13. A method according to claim 12, comprising activating thelaser radiation source at a pre-determined time or following apre-determined time delay, using a timer.
 14. A method according toclaim 13, comprising activating the laser radiation source using atrigger signal from a transmitter remotely located to the apparatus. 15.A target location designation apparatus for guiding a payload to atarget location, the apparatus comprising: a laser radiation source;laser radiation reflecting arrangement including at least one of agrating and dispersive element, and arranged to reflect laser radiationincident thereon from the laser radiation source to create reflectedlaser radiation that emits from the apparatus; an electrical powersupply including one or more batteries for powering the apparatus; andan activator for activating the laser radiation source, the activatorincluding at least one of: an electronic receiver arranged to receive awireless trigger signal for activating the laser radiation source; and atimer circuit arranged to activate the laser radiation source at apredetermined time, or following a pre-determined time delay.
 16. Thetarget location designation apparatus according to claim 15, wherein theelectrical power source further comprises a solar panel.
 17. The targetlocation designation apparatus according to claim 15, wherein the laserradiation source is configured to generate laser pulses.
 18. The targetlocation designation apparatus according to claim 15, wherein the laserradiation source is configured to generate continuous laser radiation.19. The target location designation apparatus according to claim 15,wherein the reflected laser radiation that emits from the apparatus issubstantially spatially homogenous reflected laser radiation.
 20. Amethod of guiding a payload to a target location using the targetlocation designation apparatus of claim 15, the method comprising:remotely activating the apparatus, the apparatus being located at thetarget location, thereby causing the apparatus to generate reflectedlaser radiation at the target location; and guiding the payload to thetarget location using the reflected laser radiation.